Methanol To Propylene Process Simulation And Technical Economic Analysis

As an important chemical raw material,propylene has an irreplaceable position in the chemical industry.Due to the large number of downstream products of propylene,the demand for propylene in the global market,especially in China's domestic market,continues to grow.The investment in the construction of propylene project has become an important direction for many enterprises in recent years.At present,there are many mature propylene production processes which use different raw materials.In recent years,the prices of major raw materials for propylene production such as crude oil and coal have fluctuated greatly with the influence of international situation and policies.To choose a production plan with stable and comparative raw material price is the significant content which the enterprises focus on to have profit.Methanol is an important raw material for the production of propylene.It is also an intermediate product of the coal to propylene production.Based on the methanol-to-propylene process of a company which use the technology of a German company called Lurgi,a 50 wt/a MTP process steady-state simulation process model is built by the software Unisim Design.By using the simulated information,the distillation separation sequence and the main operating parameters of the columns have been designed.And then the heat exchange network is optimized to obtain a better investment cost of the methanol route.On this basis,the investment in the project is calculated by the common project estimation method in the chemical industry.The result is accurate and reliable because the error compared with the actual data of the same process is less than 5%.By establishing a technical and economic comparison indicator system,the three propylene production routes which include methanol route,naphtha route and coal route can be compared.The naphtha route and the coal route of propylene production in the comparison are enlarged to the same scale of the methanol route.Using the same estimation method to calculate the investment for the three routes,and a linear regression was used to establish a correlation model of crude oil prices and prices of different raw materials and products.Based on the background conditions of crude oil price changes,the optimal investment plan under different crude oil prices and profit demand is found.